On Wed, Apr 11, 2012 at 04:52:32PM +0100, Russell King - ARM Linux wrote: > On Wed, Apr 11, 2012 at 10:44:22AM -0400, Nicolas Pitre wrote: > > On Wed, 11 Apr 2012, Will Deacon wrote: > > > > > If a bank of memory spanning the 4GB boundary is added on a !CONFIG_LPAE > > > kernel then we will hang early during boot since the memory bank will > > > have wrapped around to zero. > > > > > > This patch truncates memory banks for !LPAE configurations when the end > > > address is not representable in 32 bits. > > > > > > Cc: Nicolas Pitre <nico@xxxxxxxxxxx> > > > Signed-off-by: Will Deacon <will.deacon@xxxxxxx> > > > > Acked-by: Nicolas Pitre <nico@xxxxxxxxxx> > > > > Now what if start = 1G and size = 5G? The size variable is an unsigned > > long, meaning that right now the size might be truncated to 1G. > > There's a solution to that which is quite easy to do: convert the bank > information to PFNs instead of addresses. That will probably eliminate > some corner cases with partial pages which would be desirable too. Of course, what prevents us doing that conversion sanely is all the shite platform code doing crap stuff like this: arch/arm/mach-msm/board-halibut.c: mi->bank[0].start = PHYS_OFFSET; arch/arm/mach-msm/board-halibut.c: mi->bank[0].size = (101*1024*1024); which I went through everything a few years ago and eliminated all this crap. It's back now. Sod it, we'll stick with the current 4GiB limited way as long as we have platform maintainers who do this kind of crappy hack. While here, I propose to delete these: arch/arm/mach-msm/board-mahimahi.c: mi->bank[0].start = PHYS_OFFSET; arch/arm/mach-msm/board-mahimahi.c: mi->bank[0].node = PHYS_TO_NID(PHYS_OFFSET); arch/arm/mach-msm/board-mahimahi.c: mi->bank[0].size = (219*1024*1024); arch/arm/mach-msm/board-mahimahi.c: mi->bank[1].start = MSM_HIGHMEM_BASE; arch/arm/mach-msm/board-mahimahi.c: mi->bank[1].node = PHYS_TO_NID(MSM_HIGHMEM_BASE); arch/arm/mach-msm/board-mahimahi.c: mi->bank[1].size = MSM_HIGHMEM_SIZE; arch/arm/mach-msm/board-sapphire.c: mi->bank[0].start = PHYS_OFFSET; arch/arm/mach-msm/board-sapphire.c: mi->bank[0].node = PHYS_TO_NID(PHYS_OFFSET); arch/arm/mach-msm/board-sapphire.c: mi->bank[0].size = (84*1024*1024); arch/arm/mach-msm/board-sapphire.c: mi->bank[0].size = (101*1024*1024); arch/arm/mach-msm/board-sapphire.c: mi->bank[0].size = (101*1024*1024); because they haven't been buildable since 7th May 2010 (that's 23 months ago), and no one has reported any build errors with them. They're only receiving updates from other sweeps and nothing more. This all means no one is even attempting to build this code. It's pointless having unbuildable code in the kernel, and it's nothing more than a useless maintanence burden. -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
